The “Big 72-Hour Sale” features discounted tickets for nonstop roundtrip travel across the country.

Some of the biggest savings include:

18 destinations within 500 miles, including Boston and Charlotte, for $98.

Washington D.C. to parts of Florida for $198.

Coast-to-coast flights for $298.

The prices also include all government taxes and fees. Tom Parsons, with BestFares.com, says that’s a steal.

“You may not see these airfares repeated again in 2013… This is what you write home to mom about.”

While tickets can be booked between Tuesday and midnight Thursday, Parsons suggests Wednesday morning will be the sweet spot to buy.

“We do expect the competition like United, Delta, and U.S. Airways to match them,” Parsons says. “You still may want to wait and see who gives you the best options.”

But, he says, avoid holding out until later in the summer because prices will skyrocket. “You’re going to have to beg, borrow, and steal and hope you can get somewhere at a very reasonable price,” Parsons says.

Travel dates must fall between Aug. 26 and Dec. 18. Discount prices are not guaranteed for Friday and Sunday flights. The only blackout dates that apply are Sept. 2 and Nov. 26 through Dec. 3.